Ignition System: Description and Operation

Ignition System Description

The ignition system is of an electronic ignition type that has neither distributor nor high-tension cords. It consists of the following parts:

- ECM
ECM monitors engine and vehicle conditions through the signals from the relevant sensors, determines the most suitable ignition timing and sends control signals to ignition coil assemblies.
- Ignition coil assembly
The ignition coil assembly is a combination of an ignitor and ignition coils. It is provided for each cylinder and the ignition coils fit directly over each spark plug. The primary coil current is turned on and off according to the signal from the ECM. When the primary coil current is cut off, a high voltage is induced in the secondary coil. The high voltage is applied directly to the spark plug of each cylinder.
- Spark plug
- CMP sensor and CKP sensor
Using signals from these sensors, the ECM detects cylinders in which the piston is in the compression stroke and detects the crank angle, and sets the initial ignition timing.
- TP sensor, ECT sensor, MAF sensor, IAT sensor, knock sensor and other sensors/switches
Using signals from these sensors/switches, the ECM corrects the initial ignition timing and sets the optimum timing according to the engine conditions.